有功电流与()产生的功率称为有功功率。
A.电压
B.电量
C.电阻
D.电功率
参考答案:A
I looked out and found the ground ______ with white snow. [ ]
A. covered
B. covering
C. to cover
D. is covered
下列试验中用于诊断胰腺疾病的试验是()
A.促胰酶素-促胰液素试验
B.淀粉酶测定
C.隐血试验
D.电解质测定
E.胆汁测定